(rē'jŏn )

[L. regio, boundary]

A portion of the body with natural or arbitrary boundaries. SYN: regio.

regional,

(rē'jŏ-năl )

abdominal r.sThe abdomen and its external surface, divided into nine regions by four imaginary planes: two horizontal (one at the inferiormost point of the costal margin and the other at the level of the iliac crest); and two vertical midclavicular lines. The regions and their contents include the: 1) right hypochondriac (right kidney, right lobe of the liver, gall bladder, duodenum, hepatic flexure); 2) epigastric (inferiormost esophagus, stomach, liver, transverse colon, part of the small intestine, pancreas, left and right suprarenal gland s, parts of the left and right kidneys and ureters); 3) left hypochondriac (stomach, splenic flexure, spleen, part of the small intestine, left kidney); 4) right lumbar (gall bladder, part of small intestine, ascending colon, right kidney); 5) umbilical (transverse colon, stomach, part of small intestine, pancreas, portions of left and right kidneys, cisterna chyli); 6) left lumbar (part of small intestine, descending colon, left kidney); 7) right iliac (cecum, ascending colon, appendix, right ovary and uterine tube); 8) hypogastric (sigmoid colon, rectum, part of small intestine, right and left ureters, urinary bladder, uterus, seminal vesicles, prostate); and 9) left iliac (sigmoid colon, descending colon, part of the small intestine, left ovary and uterine tube).

SEE: illus.

chest r.Any of the three areas of the chest: anterior, posterior, and lateral. The anterior divisions (right and left) are the clavicular, infraclavicular, and supraclavicular, the mammary and inframammary, and the upper and lower sternal. The posterior divisions (right and left) are the scapular, infrascapular, interscapular, and suprascapular. The lateral divisions are the axillary and infra-axillary.

epigastric r.Epigastric fossa.

hypochondriac r.Hypochondrium.

hypogastric r.Hypogastrium.

iliac r.The inguinal region on either side of the hypogastrium.

inguinal r.Groin.

r. of interest

ABBR: ROI

lateral cervical r.Posterior cervical triangle

lumbar r.That area of the abdominal surface lateral to the umbilical region, above the iliac region, and below the hypochondriac region.

parasternal r.The area between the sternal border and parasternal line.

sternomastoid r.The wide area on the lateral region of the neck covered by sternocleidomastoid muscle.